From December 1, 2022, to January 31, 2023, we continuously collected data from 4,077 patients with COVID-19 in our hospital. A total of 2,862 patients were included in this study after exclusion, with 1,372 patients receiving azvudine treatment and another 1,490 patients receiving standard treatment. The flowchart of the entire study process is detailed in Fig. 1. Table 1 displays the baseline demographic and clinical characteristics of the patients. The preliminary data indicate differences in several variables between the two groups. By adjusting variables with p < 0.05 in the univariate Cox regression analysis (S1) and conducting 1:1 PSM matching, we ultimately identified data from 920 patients receiving azvudine treatment and 920 patients in the control group for analysis. The baseline characteristics of the two groups remained balanced with a standardized mean difference (SMD) < 0.1(S2, S4). After IPTW matching, a total of 2,867 azvudine-treated patients and 2,877 patients receiving standard treatment were included, with an SMD < 0.1(S3, S4).
Table 1
Characteristics of the patients with COVID-19
Variables | Total (n = 2862) | Control group (n = 1372) | Azvudine group(n = 1490) | p |
29 days survival,n (%) | | | | 0.937 |
No | 2715 (94.9) | 1302 (94.9) | 1413 (94.8) | |
Yes | 147 (5.1) | 70 (5.1) | 77 (5.2) | |
Hospital days | 10.47 ± 6.43 | 9.03 ± 6.70 | 11.79 ± 5.87 | < 0.001 |
Gender, n (%) | | | | < 0.001 |
Men | 1654 (57.8) | 715 (52.1) | 939 (63) | |
Women | 1208 (42.2) | 657 (47.9) | 551 (37) | |
Age | 65.19 ± 16.99 | 61.71 ± 18.49 | 68.41 ± 14.78 | < 0.001 |
BMI | 23.17 ± 3.99 | 23.03 ± 4.15 | 23.32 ± 3.83 | 0.137 |
Cardiovascular diseases,n (%) | | | | 0.091 |
No | 2512 (87.8) | 1219 (88.8) | 1293 (86.8) | |
Yes | 350 (12.2) | 153 (11.2) | 197 (13.2) | |
Hypertension,n (%) | | | | < 0.001 |
No | 1636 (57.2) | 843 (61.4) | 793 (53.2) | |
Yes | 1226 (42.8) | 529 (38.6) | 697 (46.8) | |
Diabetes mellitus,n (%) | | | | < 0.001 |
No | 2269 (79.3) | 1138 (82.9) | 1131 (75.9) | |
Yes | 593 (20.7) | 234 (17.1) | 359 (24.1) | |
Chronic kidney disease,n (%) | | | | 0.070 |
No | 2538 (88.7) | 1232 (89.8) | 1306 (87.7) | |
Yes | 324 (11.3) | 140 (10.2) | 184 (12.3) | |
Chronic obstructive pulmonary disease,n (%) | | | | 0.043 |
No | 2499 (87.3) | 1216 (88.6) | 1283 (86.1) | |
Yes | 363 (12.7) | 156 (11.4) | 207 (13.9) | |
Cancer,n (%) | | | | < 0.001 |
No | 2477 (86.5) | 1137 (82.9) | 1340 (89.9) | |
Yes | 385 (13.5) | 235 (17.1) | 150 (10.1) | |
Clinical stages,n (%) | | | | < 0.001 |
Mild | 842 (29.4) | 637 (46.4) | 205 (13.8) | |
Moderate | 1585 (55.4) | 598 (43.6) | 987 (66.2) | |
Severe | 329 (11.5) | 95 (6.9) | 234 (15.7) | |
Critical | 106 (3.7) | 42 (3.1) | 64 (4.3) | |
White blood cells (109/L) | 7.10 ± 4.71 | 7.09 ± 5.20 | 7.11 ± 4.21 | 0.920 |
Red blood cells (1012/L) | 4.08 ± 0.85 | 4.12 ± 0.86 | 4.05 ± 0.84 | 0.033 |
Hemoglobin (g/L) | 120.18 ± 23.76 | 120.71 ± 23.79 | 119.69 ± 23.73 | 0.251 |
Platelets (109/L) | 225.84 ± 107.35 | 225.57 ± 108.12 | 226.09 ± 106.68 | 0.896 |
Neutrophil (109/L) | 5.31 ± 4.39 | 5.20 ± 4.89 | 5.41 ± 3.86 | 0.190 |
Lymphocyte (109/L) | 1.11 ± 0.91 | 1.17 ± 0.72 | 1.06 ± 1.05 | < 0.001 |
Monocyte (109/L) | 0.60 ± 0.63 | 0.64 ± 0.80 | 0.57 ± 0.41 | 0.009 |
Eosinophil (109/L) | 0.06 ± 0.11 | 0.07 ± 0.12 | 0.05 ± 0.10 | < 0.001 |
Basophil (109/L) | 0.02 ± 0.03 | 0.02 ± 0.03 | 0.01 ± 0.03 | < 0.001 |
Alanine aminotransferase (U/L) | 30.34 ± 81.87 | 29.58 ± 69.49 | 31.04 ± 91.83 | 0.629 |
Aspartate aminotransferase (U/L) | 43.30 ± 263.01 | 48.70 ± 361.29 | 38.32 ± 112.60 | 0.308 |
Glutamyl transpeptidase (U/L) | 44.63 ± 74.88 | 43.74 ± 75.19 | 45.45 ± 74.62 | 0.542 |
Alkaline phosphatase (U/L) | 82.56 ± 56.86 | 86.15 ± 66.99 | 79.25 ± 45.36 | 0.001 |
Cholinesterase (U/L) | 6090.21 ± 2077.49 | 6339.82 ± 2121.92 | 5860.38 ± 2009.19 | < 0.001 |
Total protein (g/L) | 62.52 ± 7.25 | 63.44 ± 7.29 | 61.68 ± 7.12 | < 0.001 |
Albumin (g/L) | 35.62 ± 5.52 | 36.76 ± 5.44 | 34.58 ± 5.38 | < 0.001 |
Globulin (g/L) | 26.89 ± 5.31 | 26.65 ± 5.65 | 27.10 ± 4.97 | 0.023 |
Total bilirubin (µmol/L) | 12.23 ± 17.39 | 13.24 ± 22.53 | 11.31 ± 10.56 | 0.004 |
Direct bilirubin (µmol/L) | 6.42 ± 13.74 | 7.02 ± 17.80 | 5.87 ± 8.40 | 0.029 |
Indirect bilirubin (µmol/L) | 5.99 ± 7.48 | 6.28 ± 6.35 | 5.71 ± 8.38 | 0.041 |
Total bile acid (µmol/L) | 7.46 ± 18.67 | 8.08 ± 21.51 | 6.88 ± 15.58 | 0.092 |
Prealbumin (mg/L) | 162.24 ± 79.59 | 177.45 ± 80.50 | 148.24 ± 76.12 | < 0.001 |
Alpha-fucosidase (U/L) | 23.21 ± 10.46 | 23.96 ± 10.99 | 22.51 ± 9.90 | < 0.001 |
Urea (mmol/L) | 7.56 ± 8.25 | 6.94 ± 6.13 | 8.14 ± 9.76 | < 0.001 |
Creatinine (µmol/L) | 133.96 ± 202.80 | 122.87 ± 178.85 | 144.17 ± 222.15 | 0.005 |
Glomerular filtration rate(ml/min*1.73m2) | 100.00 ± 47.32 | 104.25 ± 47.97 | 96.09 ± 46.38 | < 0.001 |
Uric acid (µmol/L) | 306.71 ± 132.41 | 311.28 ± 129.76 | 302.51 ± 134.72 | 0.076 |
Total carbon dioxide (mmol/L) | 24.23 ± 11.37 | 24.48 ± 9.57 | 24.00 ± 12.81 | 0.252 |
Prothrombin time (s) | 12.00 ± 2.83 | 11.90 ± 1.99 | 12.09 ± 3.43 | 0.073 |
International standardization ratio | 1.20 ± 6.96 | 1.02 ± 0.18 | 1.36 ± 9.64 | 0.177 |
Fibrinogen (g/l) | 4.18 ± 2.62 | 3.79 ± 1.33 | 4.54 ± 3.35 | < 0.001 |
Activated partial thromboplastin time (s) | 29.74 ± 9.33 | 29.34 ± 6.43 | 30.11 ± 11.35 | 0.025 |
Thrombin time (s) | 16.41 ± 8.77 | 16.46 ± 8.80 | 16.36 ± 8.73 | 0.777 |
Antithrombin-III (%) | 83.92 ± 15.86 | 85.04 ± 16.81 | 82.90 ± 14.87 | < 0.001 |
Prothrombin activity (%) | 83.75 ± 15.49 | 84.48 ± 15.86 | 83.08 ± 15.12 | 0.016 |
D-dimer (mg/L) | 2.07 ± 5.50 | 2.06 ± 5.95 | 2.08 ± 5.04 | 0.929 |
Data are n (%) or median (IQ |
Our main objective was to investigate the association between azvudine treatment and the 28-day mortality rate among hospitalized patients with COVID-19. In the original cohort analysis, no significant impact on the 28-day mortality rate of hospitalized patients with COVID-19 were observed (15.8% vs. 21.8%, p = 0.065) (Fig. 2A). However, after PSM and IPTW adjustments, azvudine significantly improved the 28-day mortality rate in hospitalized patients with COVID-19 (20.9% vs. 19.2%, p = 0.003 and 21.8% vs. 23.7%, p = 0.039, respectively) (Figs. 2B and 2C).
To further investigate the relationship between azvudine treatment and patient mortality rates, this study compared patients in different clinical subtypes, which showed that in patients with mild COVID-19, azvudine treatment did not significantly alter the 28-day mortality rate (3.3% vs. 21.0%, p = 0.086) (Fig. 3A). However, in patients with moderate (12.9% vs. 9.5%, p = 0.043), severe (37.2% vs. 39.8%, p = 0.014), and critical (64.9% vs. 46.4%, p = 0.008) conditions, patients receiving azvudine intervention exhibited significantly different 28-day survival rates compared to those receiving standard treatment (Figs. 3B, 3C, and 3D). When azvudine was administered to severe and critical patients, there was a more significant reduction in mortality rates at 7 days (10.1% vs. 1.7% and 34.7% vs. 8.1%, respectively) and 14 days (23.0% vs. 8.4% and 46.5% vs. 22.9%, respectively) (Figs. 3C and 3D). These data show that azvudine can improve the survival rates of patients with COVID-19, particularly for severe and critical patients.
Based on Cox regression analysis, in the original cohort, azvudine treatment reduced 7-day (1.09/1000 people vs. 5.06/1000 people, p < 0.001) and 14-day (3.35/1000 people vs. 5.65/1000 people, p = 0.001) mortality rates. However, the effect on 28-day mortality (4.38/1000 people vs. 5.65/1000 people, p = 0.065) was not significant (Table 2). Post-propensity score matching (PSM), the azvudine group demonstrated significantly improved all-cause mortality rates at 7 days (0.80/1000 people vs. 6.29/1000 people, p < 0.001), 14 days (3.42/1000 people vs. 7.26/1000 people, p < 0.01), and 28 days (4.33/1000 people vs. 7.29/1000 people, p = 0.003). This finding aligns with results following inverse probability of treatment weighting (IPTW) adjustment, where all-cause mortality rates at 7, 14, and 28 days in the azvudine group and control group were 0.93/1000 and 7.07/1000 people (p < 0.001), 3.87/1000 and 7.62/1000 people (p = 0.001), and 5.15/1000 and 7.69/1000 people (p = 0.039), respectively. Subgroup analysis based on COVID-19 clinical grading revealed that in mild patients, azvudine reduced mortality within 7 days (HR: 0.04, 95% CI: 0.00-0.74, p = 0.030), but not significantly at 14 days (HR: 1.02, 95% CI: 0.34–3.07, p = 0.968) or 28 days (HR: 0.98, 95% CI: 0.34–2.84, p = 0.966). In moderate, severe, and critical patients, azvudine significantly reduced mortality rates at 7, 14, and 28 days, with greater effectiveness observed in critical patients.
Table 2
Comparison of mortality rates between Azvudine and conventional treatment groups using COX regression analysis
Variable | rate per 1000 person-days of Control | rate per 1000 person-days of azvudine | P of logrank | HR | adj.HR |
Overall | | | | | |
Before PSM | | | | | |
7-day | 5.06 (3.48 to 6.65) | 1.09 (0.45 to 1.73) | < 0.001 | 0.20(0.10–0.40); P < 0.001 | 0.11(0.05–0.24); P < 0.001 |
14-day | 5.65 (4.22 to 7.07) | 3.35 (2.43 to 4.26) | 0.001 | 0.54(0.37–0.79); P = 0.001 | 0.34(0.23–0.52); P < 0.001 |
28-day | 5.65 (4.33 to 6.97) | 4.38 (3.41 to 5.36) | 0.065 | 0.74(0.53–1.02); P = 0.067 | 0.43(0.30–0.62); P < 0.001 |
After PSM | | | | | |
7-day | 6.29 (4.18 to 8.40) | 0.80 (0.10 to 1.51) | < 0.001 | 0.12(0.05–0.32); P < 0.001 | - |
14-day | 7.26 (5.35 to 9.17) | 3.42 (2.24 to 4.60) | < 0.001 | 0.44(0.28–0.68); P < 0.001 | - |
28-day | 7.29 (5.51 to 9.07) | 4.33 (3.10 to 5.57) | 0.003 | 0.57(0.39–0.83); P = 0.003 | - |
After IPTW | | | | | |
7-day | 7.07 (5.80 to 8.34) | 0.93 (0.50 to 1.36) | < 0.001 | 0.13(0.06–0.25); P < 0.001 | - |
14-day | 7.61 (6.50 to 8.72) | 3.87 (3.16 to 4.59) | 0.001 | 0.48(0.31–0.75); P = 0.001 | - |
28-day | 7.69 (6.65 to 8.72) | 5.15 (4.39 to 5.91) | 0.039 | 0.65(0.42-1.00); P = 0.048 | - |
clinical typing-I | | | | | |
7-day | 3.02 (1.15 to 4.89) | 0.72 (-0.69 to 2.14) | 0.107 | 0.21(0.03–1.69); P = 0.144 | 0.04(0.00-0.74); P = 0.030 |
14-day | 2.49 (1.02 to 3.95) | 4.43 (1.54 to 7.31) | 0.257 | 1.66(0.69–4.03); P = 0.261 | 1.02(0.34–3.07); P = 0.968 |
28-day | 2.14 (0.87 to 3.40) | 4.72 (1.94 to 7.51) | 0.086 | 2.06(0.89–4.76); P = 0.093 | 0.98(0.34–2.84); P = 0.966 |
clinical typing-II | | | | | |
7-day | 1.68 (0.34 to 3.03) | 0.15 (-0.14 to 0.44) | 0.003 | 0.08(0.01–0.68); P = 0.020 | 0.00(0.00–0.00); P < 0.001 |
14-day | 2.87 (1.37 to 4.37) | 1.54 (0.76 to 2.31) | 0.038 | 0.47(0.23–0.98); P = 0.043 | 0.41(0.18–0.96); P = 0.039 |
28-day | 3.23 (1.74 to 4.72) | 1.82 (1.02 to 2.62) | 0.043 | 0.52(0.28–0.99); P = 0.047 | 0.48(0.23-1.00); P = 0.049 |
clinical typing-III | | | | | |
7-day | 14.59 (5.13 to 24.05) | 2.49 (0.05 to 4.93) | 0.001 | 0.17(0.05–0.54); P = 0.003 | 0.07(0.01–0.89); P = 0.040 |
14-day | 17.36 (9.18 to 25.55) | 5.22 (2.49 to 7.95) | < 0.001 | 0.29(0.14–0.58); P = 0.001 | 0.28(0.11–0.72); P = 0.008 |
28-day | 16.02 (8.87 to 23.17) | 7.58 (4.56 to 10.60) | 0.014 | 0.48(0.26–0.87); P = 0.016 | 0.54(0.25–1.17); P = 0.120 |
clinical typing-IV | | | | | |
7-day | 66.99 (33.09 to 100.88) | 11.36 (1.46 to 21.27) | < 0.001 | 0.18(0.06–0.49); P = 0.001 | 0.05(0.00-0.74); P = 0.029 |
14-day | 51.72 (28.46 to 74.99) | 17.08 (7.88 to 26.29) | 0.002 | 0.34(0.17–0.69); P = 0.003 | 0.37(0.14–0.99); P = 0.048 |
28-day | 46.51 (27.53 to 65.49) | 20.43 (11.98 to 28.88) | 0.008 | 0.45(0.25–0.82); P = 0.009 | 0.46(0.25–0.85); P = 0.014 |